[FFmpeg-devel] [PATCH 3/4] avcodec/dxv: Check op_offset in both directions

[Paul B Mahol]

On 9/9/19, Michael Niedermayer <michael at niedermayer.cc> wrote:
> On Fri, Jul 19, 2019 at 09:53:34PM +0200, Michael Niedermayer wrote:
>> On Fri, Jul 19, 2019 at 03:36:43PM +0200, Paul B Mahol wrote:
>> > On 7/19/19, Michael Niedermayer <michael at niedermayer.cc> wrote:
>> > > On Thu, Jun 27, 2019 at 09:32:44AM +0200, Paul B Mahol wrote:
>> > >> On 6/27/19, Michael Niedermayer <michael at niedermayer.cc> wrote:
>> > >> > Fixes: signed integer overflow: 61 + 2147483647 cannot be
>> > >> > represented
>> > >> > in
>> > >> > type 'int'
>> > >> > Fixes:
>> > >> > 15311/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DXV_fuzzer-5742552826773504
>> > >> >
>> > >> > Found-by: continuous fuzzing process
>> > >> > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
>> > >> > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
>> > >> > ---
>> > >> >  libavcodec/dxv.c | 2 +-
>> > >> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> > >> >
>> > >> > diff --git a/libavcodec/dxv.c b/libavcodec/dxv.c
>> > >> > index 5fd1844094..3506775560 100644
>> > >> > --- a/libavcodec/dxv.c
>> > >> > +++ b/libavcodec/dxv.c
>> > >> > @@ -745,7 +745,7 @@ static int dxv_decompress_cocg(DXVContext
>> > >> > *ctx,
>> > >> > GetByteContext *gb,
>> > >> >      int skip0, skip1, oi0 = 0, oi1 = 0;
>> > >> >      int ret, state0 = 0, state1 = 0;
>> > >> >
>> > >> > -    if (op_offset < 12)
>> > >> > +    if (op_offset < 12 || op_offset - 12 >
>> > >> > bytestream2_get_bytes_left(gb))
>> > >> >          return AVERROR_INVALIDDATA;
>> > >> >
>> > >> >      dst = tex_data;
>> > >> > --
>> > >> > 2.22.0
>> > >> >
>> > >> > _______________________________________________
>> > >> > ffmpeg-devel mailing list
>> > >> > ffmpeg-devel at ffmpeg.org
>> > >> > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>> > >> >
>> > >> > To unsubscribe, visit link above, or email
>> > >> > ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
>> > >>
>> > >> Make sure this does not break any files.
>> > >
>> > > Do you have any specific files i should test ?
>> > >
>> > > I of course cannot test every file on earth ...
>> >
>> > I'm on vacation, so when I get back I will give you some files.
>>
>> ok, ill wait, no hurry, enjoy your vacation!
>
> ping, this issue is reaching its deadline, so i would like to
> fix it

What deadline? Is this some kind of fancy corporation?

>
> Thanks
>
> [...]
>
>
> --
> Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
>
> When you are offended at any man's fault, turn to yourself and study your
> own failings. Then you will forget your anger. -- Epictetus
>